Radon, Thoron and Progeny Measured in Urban Health Centres and the Resulting Radiation Doses to Doctors, Nurses and Patients from the Inhalation of Air

Abstract

Doctors and nurses spent about 8 hours a day inside urban health centres examining a large number of patients. To assess radiation dose due to the attached and unattached fractions of the short-lived alpha-emitting radon decay products from the inhalation of air by working personnel and patients, concentrations of these radionuclides as well as those of radon and thoron gases were measured in indoor air of different health centres in the city of Marrakech (Morocco) by means of CR-39 and LR-115 type II solid state nuclear track detectors (SSNTDs). Committed equivalent doses per hour of exposure due to the attached and unattached fractions of 218 Po and 214 Po radon short-lived progeny were evaluated in different tissues of the respiratory tract of individuals from the inhalation of air inside the studied health centres. The influence of the activity of the attached and unattached fractions of 218 Po and 214 Po and mass of the tissue on the committed equivalent doses per hour of exposure was investigated. Annual committed effective doses due to the attached and unattached fractions of 218 Po and 214 Po radon short-lived progeny from the inhalation of air by doctors, nurses and patients inside the studied hospitals were determined. A maximum value of 7.1 mSv y-1 was found for doctors working 40 hours per week.

Assessment of Alpha Doses Received by Spa Workers Due to the Inhalation of 214Po and 218Po Radon Progeny

“…The relative error on the committed equivalent dose determination was about 10%. It has been shown in a previous work (Misdaq et al 2015b) and H u T 214Po ð Þcommitted equivalent doses depend on the integral of activity-time curves (the activity integrals) of 218 Po and 214 Po radon progeny in a given tissue of the respiratory tract, the mass of the target tissue (m T ) and the weighting factor for the partition of radiation detriment (eqns 6 and 7). Variation of the activities due to the attached and unattached fractions of 218 Po radon progeny as functions of time in various tissues of the respiratory tract from the inhalation of air by male and female spa workers in spa Room 1 are shown in 1 and 2.…”

“…The committed equivalent doses corresponding to the thoracic H TH (j') and extrathoracic H ET (j') regions of the human respiratory system are obtained by summation of regional doses weighted with factors assigned for the partition of radiation detriment are given by (Misdaq et al 2015b):…”